A Letter From Stanley Gibbons

Hey
Together with my stamps I inherited I found this letter. Together with some stamps from Bangladesh. I have tried to found out What this means but have no clue. Can someone help please

Stanley Gibbons publishes a stamp catalog, which attempts to list and describe every known valid postage stamp ever issued. Someone apparently found some stamps that weren't listed in the Gibbons catalog and sent them in to the publishers to examine. Apparently the editors examined them, found them to be genuine stamps they weren't previously aware of, and will be adding them to a future edition of the catalog. The rest of it was speculation as to how they were overlooked and how they were being used in their country of origin. The person you inherited this from was probably proud of this fact - not many collectors find unlisted stamps that go on to become listed. The letter probably has no (or very little) collectible value, but if I were in this collector's shoes, it would have a lot of sentimental value to me.

Thank you @theartfulhinger. But this doesnt means that the stamp is rare

Very few people have the luck or, in this case, the expertise in finding a new variety of stamp. The confirmation letter of a new variety from Stanley Gibbons, signed by the top man in the field,although probably not of great monetary value, is certainly worth hanging on to and even using as part of a display regarding the discovered variety. The real value is the philatelic element.

My Stanley Gibbons catalog (2007 edition) prices the stamp at UK£20 mint and UK£14 used but you should anticipate an increase in those prices in the last seven or eight years. The price would indicate a degree of rarity. A Google search might turn up an example.

I know nothing about this stamp. It's probably not rare, but it probably is relatively scarce/hard to find. But rarity or scarcity don't necessarily equate to valuable. Bangladesh isn't a real popular area to collect (i.e. there aren't many serious collectors of Bangladesh stamps), so even stamps for which there are relatively few examples will be reasonably priced in the market. Like most other things, value is determined by supply and demand. The supply of this stamp is probably pretty low, but so is demand.

Edited to add that the letter and the stamp would probably be more valuable together. If you were looking to sell, a Bangladesh specialist (if indeed there are any) would probably pay a premium, although likely not a huge one, for the "discovery copy" of that stamp. Again, there aren't that many serious collectors of Bangladesh, so the market is going to be fairly limited in any case.